Sweet potatoes (Ipomoea batatas) are believed to have originated in South America. They are in the same plant family as morning glories. Notice the similarities in the flower and leaf structure in the photo to the right.

Although some orange varieties are marketed in the U.S. as "yams", sweet potatoes are not related to true yams, which are of West African or Asian origins, and rarely found in the United States except as imports.

Cultivation of sweet potatoes in North America occurred as early as 1648 in Virginia, and reportedly taken into New England in 1764. They were grown by the Indians in the Southern U.S. in the 18th century as well.

Several months of warm weather are required to produce the sweet potatoes biggest tubers.  Northern growers can benefit from using black plastic to warm the soil for about 3 weeks prior to planting. Sweet potatoes should be planted in a ridge (raised row) to provide drainage and allow for root expansion. Space ridge about 3 1/2 feet apart with plants set 1 foot apart.

Upon receipt of your slips, placing them in a jar of water until you are ready to plant will perk them up, allow you to wait until weather conditions are perfect for your area, and give you time to prepare your soil.

Please note: Your plants may appear severely wilted which is normal, there maybe leaves that appear rotten or slimy and this is also a natural occurrence, just remove the slick or slimy leaves and place your plants in a jar of water as discussed earlier. Sweet potatoes are extremely tough and resilient plants and once livened back up will take off and grow well.

Keep transplants moist after being set in the field and water before the soil dries. Weed control will be necessary until the vines meet between the rows.

What your package may look like depending on the size of your order
The box	Inside the box	Typical 'bunch' of plants
	Plants placed in jar of water.

Harvest the tubers as soon as they have reached eating size.  They must be harvested before the vines become frosted.  If you do get an unexpected frost, dig tubers immediately as the decay in the dead vines will travel to the tubers and rotting will occur.  Sweet potatoes should not be stored at temperatures below 55ºF.  The optimal condition for storage is slightly above 55ºF and at high humidity.  Under these conditions they will store for six months.

Q.  What is the difference between a sweet potato and a yam?

A.  Decades ago, orange flesh sweet potatoes were introduced in the southern United States and farmers and shippers desired to distinguish them from the standard white flesh types. The African word "nyami" referring to the starchy, edible root of the Dioscorea genus of plants, was adopted in its English form, "yam".  Yams in the U.S. are actually sweet potatoes with relatively moist texture and orange flesh. Although the terms are generally used interchangeably, the U.S. Department of Agriculture requires that the label "yam" always be accompanied by "sweet potato."

Interesting Links:

• Sweet Potato, Commercial Vegetable Production Guides, North Willamette Research and Extension Center

• North Carolina Sweet Potatoes - Home Gardening Section

• University of Illinois Extension - Sweet Potatoes - Watch Your Garden Grow

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• Oklahoma Cooperative Extension - Sweet Potato Production - PDF

• Utah State University - Sweet Potatoes in the garden - PDF

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